I would think mountain ash or any of the crabapple varieties as well as Toba or Snowbird hawthorne, Amur cherry, pin cherry `Mary Liss`, Muckle or Princess Kay Plum would do well for you. Some of these varieties have fruit that is attractive to birds as well although you will have to consider their placement a little more carefully - ie - fruit drop and bird droppings - keep them a good distance from decks, patios, driveways, sidewalks!!!! Hope this gives you some ideas. All of these grow well in southwestern Alberta.